Comparative analysis of the leaf anatomy in two Parodiolyra species (Poaceae: Olyreae) occurring on forests in Eastern Brazil Jesus Junior, LA.a*, Oliveira, RP.a,b, Leite, KRB.a and Silva, LB.a aDepartamento de Botânica, Instituto de Biologia, Universidade Federal da Bahia – UFBA, Rua Barão de Geremoabo, 147, Campus de Ondina, CEP 40170-290, Salvador, BA, Brazil bPrograma de Pós-graduação em Botânica, Departamento de Ciências Biológicas, Universidade Estadual de Feira de Santana – UEFS, BR 116N, Km 3, CEP 44031-460, Feira de Santana, BA, Brazil *e-mail: [email protected] Received January 18, 2011 – Accepted June 7, 2011– Distributed February 29, 2012 (With 21 figures) Abstract Parodiolyra is a member of Olyreae, a tribe of herbaceous bamboo species within the Poaceae. The genus has five species, four of which were previously regarded as belonging to Olyra L. Parodiolyra has a Neotropical distribution and only two species occur on forests in Eastern Brazil: P. micrantha (Kunth) Zuloaga & Davidse and P. ramosissima (Trin.) Soderstr. & Zuloaga, the first widely distributed in the Neotropics while the second is endemic to the state of Bahia. Leaf anatomy of the two species was analysed with the aid of an optical microscope. The objective was to describe the microscopic characters and evaluate if they can be useful for the taxonomy of the genus. The observed anatomical structures did not differ from other genera of herbaceous bamboos, however some characters, both from the mesophyll and the epidermis, were useful to delimit the two species. Keywords: bambusoideae, microscopic characters, herbaceous bamboos, specific delimitation. Análise comparativa da anatomia foliar de duas espécies de Parodiolyra Soderstr. & Zuloaga (Poaceae: Olyreae) ocorrentes em florestas do leste do Brasil Resumo Parodiolyra está inserido em Olyreae, tribo de bambus herbáceos pertencente à Poaceae, e apresenta cinco espécies, sendo quatro delas previamente consideradas como parte de Olyra L. O gênero tem distribuição neotropical e apenas duas espécies ocorrem nas florestas do leste do Brasil:P. micrantha (Kunth) Zuloaga & Davidse e P. ramosissima (Trin.) Soderstr. & Zuloaga; a primeira, amplamente distribuída no Neotrópico, e a última, endêmica do Estado da Bahia. A anatomia foliar dessas duas espécies foi analisada através de microscopia de luz, com o objetivo de descrever seus caracteres microscópicos e avaliar se os mesmos podem ser úteis para a taxonomia do gênero. A estrutura anatômica observada não se diferencia daquela dos demais gêneros de bambus herbáceos, mas alguns caracteres do mesofilo e da epiderme foram úteis para delimitar as duas espécies. Palavras-chave: bambusoideae, caracteres microscópicos, bambus herbaceous, delimitação específica. 1. Introduction Parodiolyra Soderstr. & Zuloaga is a genus of herbaceous P. ramosissima (Trin.) Soderstr. & Zuloaga, P. lateralis bamboos belonging to Poaceae, Bambusoideae. The genus (J. Presl ex Nees) Soderstr. & Zuloaga and P. luetzelburgii is included in Olyreae, and has a wide distribution in the (Pilg.) Soderstr. & Zuloaga. One species was described Neotropical region, ranging from Costa Rica to Bolivia, after the creation of the genus: P. colombiensis Davidse Paraguay, Northeastern Argentina and Brazil (Oliveira & Zuloaga (Zuloaga and Davidse, 1999). Parodiolyra was and Longhi-Wagner, 2001). Parodiolyra comprises five deemed to be very close to Raddiella Swallen (Zuloaga and species, and until recently four of these species were placed Judziewicz, 1991), and this relationship has been confirmed in Olyra L. However, macromorphological characters, especially reproductive ones, were used by Soderstrom by molecular phylogenies of the group (Oliveira, 2006). and Zuloaga (1989) to justify the segregation of these All Parodiolyra species are perennial, growing in species into Parodiolyra. erect clumps, sometimes slightly decumbent or recurved, The four species formerly placed in the genus are with rarely branched culms and symmetrical, lanceolate Parodiolyra micrantha (Kunth) Zuloaga & Davidse, to broadly oval leaf blades (Oliveira and Longhi-Wagner, Braz. J. Biol., 2012, vol. 72, no. 1, p. 205-210 205 Jesus Junior, LA. et al. 2001). Inflorescences are arranged in terminal panicles, and Lençóis (R.P. Oliveira et al.139), and samples of with the lower branches having male spikelets only, and the P. ramosissima collected at Itacaré (R.P. Oliveira et al. upper branches having female spikelets only, and these are 688), Salvador (Grupo da Oceplan s/n, ALCB 19873) and characters which are widely used to characterise the genus Camamú (L.A. Mattos-Silva 4387). The voucher specimens (Oliveira, 2001). In addition, male and female spikelets are are deposited at the Herbarium of the Universidade Estadual conspicuously dimorphic, the female being larger, with de Feira de Santana (HUEFS), except the specimen collected filiform pedicels disarticulated below the two glumes, by the Grupo da Oceplan s.n., which is deposited at the which are absent in the male spikelets (Oliveira, 2001). Herbarium of the Universidade Federal da Bahia (ALCB). Parodiolyra is regarded as very heterogeneous both The leaf blades were prepared in transversal and paradermal on vegetative characters and morphology of the spikelets, sections to be observed under an optical microscope. We the latter containing very useful characters that clearly used fresh material preserved in a 70% ethanol solution delimit the species, as can be inferred in the identification whenever possible, but the majority of the material used keys shown by Soderstrom and Zuloaga (1989), Zuloaga was prepared from herbarium specimens, rehydrated with and Davidse (1999) and Oliveira (2001). However, these boiling water and glycerin (9:1), and preserved in a 70% structures are not always available in the collections found ethanol solution (Johansen, 1940). in herbaria or in the field, making it necessary to search For the anatomical analysis of both transversal and for other tools to aid in identification - for example, leaf paradermal sections, we used the middle portion of the anatomy. second leaf blade below the inflorescence. The paradermal Only two species of this genus occur in Eastern Brazil, sections were obtained by hand with a blade, or through and they were cited for the state of Bahia by Oliveira epidermis dissociation by Jeffrey’s Mixture (chromic (2001). Parodiolyra micrantha (Figures 1-2) is widely acid and nitric acid at 10%) (Johansen, 1940). In both distributed in Neotropical forests (Oliveira and Longhi- procedures the samples were stained with a 1% solution of Wagner 2001), being one of the most common species hydroalcoholic safranin. To obtain the cross sections, the of herbaceous bamboos across the state. The species material was embedded in paraffin according to Sass (1940) possess great ecological amplitude, being found at the and sectioned in a rotatory microtome. The paradermal edges of rainforests, riparian forests, marshes and even in and transversal sections were mounted using glycerin the highland areas of the Chapada Diamantina (Oliveira, jelly and Entellan respectively (Kraus and Arduin, 1997). P. ramosissima 2001). On the other hand, (Figures 3-4) is All slides prepared were observed, measured and endemic to Bahia, being found predominantly in low-lying photographed in an optical microscope. To verify that coastal forests and sand dune vegetation of the southern region of the state, in the sand dunes of Salvador and in the humid forests of the Serra da Jibóia (Oliveira 2001). As common in other Poaceae, bamboos have similar characters of leaf anatomy, such as fusiform and arm cells in the chlorenchyma, not radiate mesophyll and two-celled trichomes of the Panicum type (GPWG 2001). However, the effectiveness of these and other characters for the taxonomy of the group has been little evaluated, especially with regard to herbaceous groups. The available literature indicates that these characters can vary little within a genus, as indicated in Oliveira et al. (2008a) for Raddia Bertol., or they can vary considerably and even help in specific delimitation, as for instance withinPariana Aubl. in Eastern Brazil (Oliveira et al., 2008b). The data analysed here represent the first formal description of leaf anatomy of members of Parodiolyra, contributing to increase the knowledge about the group. Our main objective was to examine the leaf anatomy of representatives of this genus occurring in forests of Eastern Brazil, based on samples collected in the state of Bahia, in order to evaluate the efficiency of leaf microscopic characters for specific delimitation in the group. Figures 1-4. Representatives of Parodiolyra Soderstr. & Zuloaga used in this study. 1-2: P. micrantha (Kunth) 2. Materials and methods Zuloaga & Davidse: 1) Habit; 2) Inflorescences, the left one a young inflorescence (Oliveira et al. 239 (HUEFS); We analysed the second leaf blade above the inflorescence 3-4) Inflorescence of P. ramosissima (Trin.) Soderstr. & on samples of Parodiolyra micrantha, from Salvador Zuloaga: (M.M. Silva et al. 369 (HUEFS). Bars 1 = 5 cm; (L. Noblick 1625), Igrapiúna (R.P. Oliveira et al. 1368) 2 = 2,5 cm; 3 = 3,5 cm; 4 = 1,5 cm. 206 Braz. J. Biol., 2012, vol. 72, no. 1, p. 205-210 Leaf anatomy in two Parodiolyra (Poaceae: Olyreae) microtypes observed in both species were significantly trichomes (microhairs) (Figure 13), which were found in different, measurements of epidermal cells and fusiform both species and on both surfaces, with higher density on